Systems and methods for power efficient discovery of infrastructure services on a network

ABSTRACT

Systems, methods, and devices for power-efficient discovery of infrastructure services on a network are disclosed. In one aspect, a method for using advertising windows to transmit service information on a network is disclosed. The method includes transmitting timing information regarding an advertising window during which information on services offered by one or more nodes on the network will be advertised. The method further includes during the advertising window, transmitting information on services offered by one or more nodes on the network.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. application Ser.No. 14/228,026, filed Mar. 27, 2014, and entitled SYSTEMS AND METHODSFOR POWER EFFICIENT DISCOVERY OF INFRASTRUCTURE SERVICES ON A NETWORK,”which claims priority to Provisional Application No. 61/807,904 entitled“SYSTEMS AND METHODS FOR POWER EFFICIENT DISCOVERY OF INFRASTRUCTURESERVICES ON A NETWORK” filed Apr. 3, 2013, and assigned to the assigneehereof. The disclosures of these priori applications are considered partof this application, and are hereby incorporated by reference in theirentirety.

BACKGROUND

Field

The present application relates generally to wireless communications,and more specifically to systems, methods, and devices for powerefficient discovery of infrastructure services on a network.

Background

In many telecommunication systems, communications networks are used toexchange messages among several interacting spatially-separated devices.Networks may be classified according to geographic scope, which couldbe, for example, a metropolitan area, a local area, or a personal area.Such networks would be designated respectively as a wide area network(WAN), metropolitan area network (MAN), local area network (LAN),wireless local area network (WLAN), or personal area network (PAN).Networks also differ according to the switching/routing technique usedto interconnect the various network nodes and devices (e.g. circuitswitching vs. packet switching), the type of physical media employed fortransmission (e.g. wired vs. wireless), and the set of communicationprotocols used (e.g. Internet protocol suite, SONET (Synchronous OpticalNetworking), Ethernet, etc.).

Wireless networks are often preferred when the network elements aremobile and thus have dynamic connectivity needs, or if the networkarchitecture is formed in an ad hoc, rather than fixed, topology.Wireless networks employ intangible physical media in an unguidedpropagation mode using electromagnetic waves in the radio, microwave,infra-red, optical, etc. frequency bands. Wireless networksadvantageously facilitate user mobility and rapid field deployment whencompared to fixed wired networks.

The devices in a wireless network may transmit/receive informationbetween each other. In general, some devices may serve as access points(APs) for a network, which other devices may connect to access functionsof the network. Different APs may offer varying services to devicesconnected to those APs. Thus, improved systems, methods and devices forproviding a low overhead method for APs to advertise a collection ofservices which may be accessed through the AP are desired.

SUMMARY

The systems, methods, and devices of the invention each have severalaspects, no single one of which is solely responsible for its desirableattributes. Without limiting the scope of this invention as expressed bythe claims which follow, some features will now be discussed briefly.After considering this discussion, and particularly after reading thesection entitled “Detailed Description” one will understand how thefeatures of this invention provide advantages that include improvedpaging for devices in a wireless network.

In some aspects, a method for using advertising windows to transmitservice information on a network is disclosed. The method comprisestransmitting timing information regarding an advertising window duringwhich information on services offered by one or more nodes on thenetwork will be advertised; and during the advertising window,transmitting information on services offered by one or more nodes on thenetwork.

Parts of the disclosure disclose a wireless communication device. Thedevice comprises a transmitter, the transmitter configured to transmittiming information regarding an advertising window during whichinformation on services offered by one or more nodes on the network willbe advertised; and during the advertising window, transmit informationon services offered by one or more nodes on the network.

In some aspects, a wireless communication device is disclosed. Thedevice comprises means for transmitting timing information regarding anadvertising window during which information on services offered by oneor more nodes on the network will be advertised; and means fortransmitting information on services offered by one or more nodes on thenetwork during the advertising window.

In some aspects, a non-transitory, computer readable medium comprisinginstructions that when executed cause a processor in a device to performa method for using advertising windows to transmit service informationon a network is disclosed. The method comprises transmitting timinginformation regarding an advertising window during which information onservices offered by one or more nodes on the network will be advertised;and during the advertising window, transmitting information on servicesoffered by one or more nodes on the network.

In some aspects, a method for using advertising windows on a network isdisclosed. The method comprises receiving timing information from anaccess point regarding an advertising window during which information onservices offered by one or more nodes on the network will be advertised;and during the advertising window, receiving information from the accesspoint on services offered by one or more nodes on the network.

In some aspects, a wireless communication device is disclosed. Thedevice comprises a receiver configured to receive timing informationfrom an access point regarding an advertising window during whichinformation on services offered by one or more nodes on the network willbe advertised; and during the advertising window, receive informationfrom the access point on services offered by one or more nodes on thenetwork.

In some aspects, a wireless communication device is disclosed. Thedevice comprises means for receiving timing information from an accesspoint regarding an advertising window during which information onservices offered by one or more nodes on the network will be advertised;and means for receiving information from the access point on servicesoffered by one or more nodes on the network during the advertisingwindow.

In some aspects, a non-transitory, computer readable medium comprisinginstructions that when executed cause a processor in a device to performa method for using advertising windows on a network is disclosed. Themethod comprises receiving timing information from an access pointregarding an advertising window during which information on servicesoffered by one or more nodes on the network will be advertised; andduring the advertising window, receiving information from the accesspoint on services offered by one or more nodes on the network.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an example wireless communication system in which aspectsof the present disclosure may be employed.

FIG. 2 shows a functional block diagram of an example wireless devicethat may be employed within the wireless communication system of FIG. 1.

FIG. 3 is a flowchart of a method for using advertising windows totransmit service information on a network, which may be used on an APsuch as AP 104.

FIG. 4 is a flowchart of a method for using advertising windows on anetwork, which may be used on a STA such as STA 106.

DETAILED DESCRIPTION

Various aspects of the novel systems, apparatuses, and methods aredescribed more fully hereinafter with reference to the accompanyingdrawings. This disclosure may, however, be embodied in many differentforms and should not be construed as limited to any specific structureor function presented throughout this disclosure. Rather, these aspectsare provided so that this disclosure will be thorough and complete, andwill fully convey the scope of the disclosure to those skilled in theart. Based on the teachings herein one skilled in the art shouldappreciate that the scope of the disclosure is intended to cover anyaspect of the novel systems, apparatuses, and methods disclosed herein,whether implemented independently of, or combined with, any other aspectof the invention. For example, an apparatus may be implemented or amethod may be practiced using any number of the aspects set forthherein. In addition, the scope of the invention is intended to coversuch an apparatus or method which is practiced using other structure,functionality, or structure and functionality in addition to or otherthan the various aspects of the invention set forth herein. It should beunderstood that any aspect disclosed herein may be embodied by one ormore elements of a claim.

Although particular aspects are described herein, many variations andpermutations of these aspects fall within the scope of the disclosure.Although some benefits and advantages of the preferred aspects arementioned, the scope of the disclosure is not intended to be limited toparticular benefits, uses, or objectives. Rather, aspects of thedisclosure are intended to be broadly applicable to different wirelesstechnologies, system configurations, networks, and transmissionprotocols, some of which are illustrated by way of example in thefigures and in the following description of the preferred aspects. Thedetailed description and drawings are merely illustrative of thedisclosure rather than limiting, the scope of the disclosure beingdefined by the appended claims and equivalents thereof.

Popular wireless network technologies may include various types ofwireless local area networks (WLANs). A WLAN may be used to interconnectnearby devices together, employing widely used networking protocols. Thevarious aspects described herein may apply to any communicationstandard, such as a wireless protocol.

In some aspects, wireless signals in a sub-gigahertz band may betransmitted according to the 802.11ah protocol using orthogonalfrequency-division multiplexing (OFDM), direct-sequence spread spectrum(DSSS) communications, a combination of OFDM and DSSS communications, orother schemes. Implementations of the 802.11ah protocol may be used forsensors, metering, and smart grid networks. Advantageously, aspects ofcertain devices implementing the 802.11ah protocol may consume lesspower than devices implementing other wireless protocols, and/or may beused to transmit wireless signals across a relatively long range, forexample about one kilometer or longer.

In some implementations, a WLAN includes various devices which are thecomponents that access the wireless network. For example, there may betwo types of devices: access points (“APs”) and clients (also referredto as stations, or “STAs”). In general, an AP may serve as a hub or basestation for the WLAN and a STA serves as a user of the WLAN. Forexample, a STA may be a laptop computer, a personal digital assistant(PDA), a mobile phone, etc. In an example, a STA connects to an AP via aWiFi (e.g., IEEE 802.11 protocol such as 802.11ah) compliant wirelesslink to obtain general connectivity to the Internet or to other widearea networks. In some implementations a STA may also be used as an AP.

An AP may also comprise, be implemented as, or known as a NodeB, RadioNetwork Controller (“RNC”), eNodeB, Base Station Controller (“BSC”),Base Transceiver Station (“BTS”), Base Station (“BS”), TransceiverFunction (“TF”), Radio Router, Radio Transceiver, or some otherterminology.

A STA may also comprise, be implemented as, or known as an accessterminal (“AT”), a subscriber station, a subscriber unit, a mobilestation, a remote station, a remote terminal, a user terminal, a useragent, a user device, user equipment, or some other terminology. In someimplementations an access terminal may comprise a cellular telephone, acordless telephone, a Session Initiation Protocol (“SIP”) phone, awireless local loop (“WLL”) station, a personal digital assistant(“PDA”), a handheld device having wireless connection capability, orsome other suitable processing device connected to a wireless modem.Accordingly, one or more aspects taught herein may be incorporated intoa phone (e.g., a cellular phone or smartphone), a computer (e.g., alaptop), a portable communication device, a headset, a portablecomputing device (e.g., a personal data assistant), an entertainmentdevice (e.g., a music or video device, or a satellite radio), a gamingdevice or system, a global positioning system device, or any othersuitable device that is configured to communicate via a wireless medium.

As discussed above, certain of the devices described herein mayimplement the 802.11ah standard, for example. Such devices, whether usedas a STA or an AP or other device, may be used for smart metering or ina smart grid network. Such devices may provide sensor applications or beused in home automation. The devices may also be used in a healthcarecontext, such as for personal healthcare. They may also be used forsurveillance, to enable extended-range Internet connectivity (forexample, for use with hotspots), or to implement machine-to-machinecommunications.

FIG. 1 shows an exemplary wireless communication system 100 in whichaspects of the present disclosure may be employed. The wirelesscommunication system 100 may operate pursuant to a wireless standard,for example the 802.11ah standard. The wireless communication system 100may include an AP 104, which communicates with STAs 106.

A variety of processes and methods may be used for transmissions in thewireless communication system 100 between the AP 104 and the STAs 106.For example, signals may be sent and received between the AP 104 and theSTAs 106 in accordance with OFDM or orthogonal frequency-divisionmultiple access (OFDMA) techniques. If this is the case, the wirelesscommunication system 100 may be referred to as an OFDM/OFDMA system.Alternatively, signals may be sent and received between the AP 104 andthe STAs 106 in accordance with code division multiple access (CDMA)techniques. If this is the case, the wireless communication system 100may be referred to as a CDMA system.

A communication link that facilitates transmission from the AP 104 toone or more of the STAs 106 may be referred to as a downlink (DL) 108,and a communication link that facilitates transmission from one or moreof the STAs 106 to the AP 104 may be referred to as an uplink (UL) 110.Alternatively, a downlink 108 may be referred to as a forward link or aforward channel, and an uplink 110 may be referred to as a reverse linkor a reverse channel.

The AP 104 may act as a base station and provide wireless communicationcoverage in a basic service area (BSA) 102. The AP 104 along with theSTAs 106 associated with the AP 104 and that use the AP 104 forcommunication may be referred to as a basic service set (BSS). It shouldbe noted that the wireless communication system 100 may not have acentral AP 104, but rather may function as a peer-to-peer networkbetween the STAs 106. Accordingly, the functions of the AP 104 describedherein may alternatively be performed by one or more of the STAs 106.

The AP 104 may transmit a beacon signal (or simply a beacon), via acommunication link such as the downlink 108, to other STAs 106 of thesystem 100, which may help the other STAs 106 to synchronize theirtiming with the AP 104, or which may provide other information orfunctionality. Such beacons may be transmitted periodically. In oneaspect, the period between successive beacons may be referred to as asuperframe. The time period between transmissions of beacons may bedivided into a number of groups or intervals. In one aspect, the beaconmay include, but is not limited to, such information as timestampinformation to set a common clock between a number of devices on thenetwork, a peer-to-peer network identifier, a device identifier,capability information, a superframe duration, transmission directioninformation, reception direction information, a neighbor list, and/or anextended neighbor list. Some of these are described in additional detailbelow. Thus, a beacon may include both common (e.g. shared) informationamong several devices and may also include information which is specificto a given device.

In some aspects, a STA 106 may be required to associate with the AP 104in order to send communications to and/or receive communications fromthe AP 104. In one aspect, information for associating is included in abeacon which is broadcast by the AP 104. To receive such a beacon, theSTA 106 may, for example, perform a broad coverage search over acoverage region. A search may also be performed by the STA 106 bysweeping a coverage region in a lighthouse fashion, for example. Afterreceiving the information for associating, the STA 106 may transmit areference signal, such as an association probe or request, to the AP104. In some aspects, the AP 104 may use backhaul services tocommunicate with a larger network, such as the Internet or a publicswitched telephone network (PSTN).

FIG. 2 shows an example functional block diagram of a wireless device202 that may be employed within the wireless communication system 100 ofFIG. 1. The wireless device 202 is an example of a device that may beconfigured to implement the various methods described herein. Forexample, the wireless device 202 may comprise the AP 104 or one of theSTAs 106.

The wireless device 202 may include a processor 204 which controlsoperation of the wireless device 202. The processor 204 may also bereferred to as a central processing unit (CPU). Memory 206, which mayinclude both read-only memory (ROM) and random access memory (RAM), mayprovide instructions and data to the processor 204. A portion of thememory 206 may also include non-volatile random access memory (NVRAM).The processor 204 typically performs logical and arithmetic operationsbased on program instructions stored within the memory 206. Theinstructions in the memory 206 may be executable to implement themethods described herein.

The processor 204 may comprise or be a component of a processing systemimplemented with one or more processors. The one or more processors maybe implemented with any combination of general-purpose microprocessors,microcontrollers, digital signal processors (DSPs), field programmablegate array (FPGAs), programmable logic devices (PLDs), controllers,state machines, gated logic, discrete hardware components, dedicatedhardware finite state machines, or any other suitable entities that canperform calculations or other manipulations of information.

The processing system may also include machine-readable media forstoring software. Software shall be construed broadly to mean any typeof instructions, whether referred to as software, firmware, middleware,microcode, hardware description language, or otherwise. Instructions mayinclude code (e.g., in source code format, binary code format,executable code format, or any other suitable format of code). Theinstructions, when executed by the one or more processors, cause theprocessing system to perform the various functions described herein.

The wireless device 202 may also include a housing 208 that may includea transmitter 210 and/or a receiver 212 to allow transmission andreception of data between the wireless device 202 and a remote location.The transmitter 210 and receiver 212 may be combined into a transceiver214. An antenna 216 may be attached to the housing 208 and electricallycoupled to the transceiver 214. The wireless device 202 may also include(not shown) multiple transmitters, multiple receivers, multipletransceivers, and/or multiple antennas.

The transmitter 210 may be configured to wirelessly transmit messages,which may be referred to as “paging messages” that are configured toindicate to wireless devices whether or not the wireless devices need towake up from a doze state and enter an awake state as discussed below.For example, the transmitter 210 may be configured to transmit pagingmessages generated by the processor 204, discussed above. When thewireless device 202 is implemented or used as a STA 106, the processor204 may be configured to process paging messages. When the wirelessdevice 202 is implemented or used as an AP 104, the processor 204 mayalso be configured to generate paging messages. The receiver 212 may beconfigured to wirelessly receive paging messages.

The wireless device 202 may also include a signal detector 218 that maybe used in an effort to detect and quantify the level of signalsreceived by the transceiver 214. The signal detector 218 may detect suchsignals as total energy, energy per subcarrier per symbol, powerspectral density and other signals. The wireless device 202 may alsoinclude a digital signal processor (DSP) 220 for use in processingsignals. The DSP 220 may be configured to generate a packet fortransmission. In some aspects, the packet may comprise a physical layerdata unit (PPDU).

The wireless device 202 may further comprise a user interface 222 insome aspects. The user interface 222 may comprise a keypad, amicrophone, a speaker, and/or a display. The user interface 222 mayinclude any element or component that conveys information to a user ofthe wireless device 202 and/or receives input from the user.

The various components of the wireless device 202 may be coupledtogether by a bus system 226. The bus system 226 may include a data bus,for example, as well as a power bus, a control signal bus, and a statussignal bus in addition to the data bus. Those of skill in the art willappreciate the components of the wireless device 202 may be coupledtogether or accept or provide inputs to each other using some othermechanism.

Although a number of separate components are illustrated in FIG. 2, oneor more of the components may be combined or commonly implemented. Forexample, the processor 204 may be used to implement not only thefunctionality described above with respect to the processor 204, butalso to implement the functionality described above with respect to thesignal detector 218 and/or the DSP 220. Further, each of the componentsillustrated in FIG. 2 may be implemented using a plurality of separateelements.

An AP 104 may offer a wide variety of services to a STA 106. Forexample, the AP 104 may offer specialized services, such as printers,music streaming, games, or other types of services. These services maybe offered on an ad hoc basis, and may vary with time. Other devices mayalso offer services to a STA 106, and these other devices may beavailable through the network of a particular AP 104. For example, amusic streaming service may be offered by a device on the network of AP104. In any given network, different APs may offer difference servicesto STAs connected to those APs. An AP 104 may also be able to runapplications which may start or stop the offering of certain services toa STA 106. Because different services may be available through differentAPs, it may be beneficial for an AP to be configured to advertise whichservices are available through that AP. It may be beneficial for theseadvertisements to be sent during an advertising window. Such anadvertising window may allow for power-efficient discovery ofinfrastructure services. For example, such an advertising window mayalso STAs to “wake up” only during the advertising window to receive theadvertisements, rather than requiring such STAs to remain awake at alltimes in order to listen for advertisement messages.

FIG. 3 is a flowchart of a method for using advertising windows totransmit service information on a network, which may be used on an APsuch as AP 104.

At block 305, the AP transmits timing information regarding anadvertising window during which information on services offered by oneor more nodes on the network will be advertised. For example, theseadvertising windows may be periodic or may be sporadic. In some aspects,the AP may transmit timing information in a beacon frame. The AP mayalso transmit timing information as part of a probe response frame. Forexample, a device may send the AP a probe request frame requestinginformation on services offered on the network, and the AP may transmita probe response frame to that device. In some aspects, the AP may alsotransmit a minimum time to respond to a query. This time may represent aminimum time that the AP will take in order to respond to a query, wherethe response to the query may be sent in a future advertising window. Insome aspects, the AP may transmit a time to respond to the query in aprobe response frame.

At block 310, the AP transmits information on services offered by one ormore nodes on the network during the advertising window. In someaspects, the AP may also retransmit queries during the advertisingwindow. For example, the AP may receive queries at any time from otherwireless devices, and may retransmit these queries during theadvertising window. This retransmission may be beneficial, as it mayallow other devices which may offer services such as STAs to have theiradvertisement messages heard by all devices on the network. Thisretransmission may also allow devices which wish to receive informationabout services to sleep at times other than the advertisement window,without missing advertising messages. In some aspects, during theadvertising window, other devices may also transmit information onservices offered by those other devices. For example, the AP may reservea portion of the advertising window for messages from other deviceswhich may also advertise services.

It may be beneficial to send advertisements regarding services during anadvertising window. For example, the use of such an advertising windowmay minimize the number of duplicate advertisements sent to multipledevices. An advertisement window may be used to provide a low-overheadmethod for APs to advertise the collection of services that may beaccessed through the AP. These windows may reduce network overhead, byminimizing the duplication of advertisements sent to different devices,as devices may not need to request information on which services areavailable, and can instead receive this information automatically duringthe advertising window. Similarly, advertising windows may reducenetwork bandwidth use, as the AP may not need to send individualresponses to each device that requests information on a service, but caninstead respond to all such requests with one or more broadcast ormulticast messages during an advertising window. These advertisingwindows may also allow STAs to enter low-power states between theadvertising windows without missing advertising messages. Advertisementsmay be sent such that they may be received by all nearby STAs, includingthose associated with the AP, those not associated with the AP, and byother APs. These advertisements may be sent to individual devices whichrequest a listing of services, to devices which request information onthe availability of a certain service, or periodically sent to alldevices that may wish to learn which services are offered by one or moreAPs. For example, these advertisements may be multicast or broadcastmessages sent to two or more devices.

In some aspects, an AP may transmit a beacon which contains timinginformation regarding an advertisement window. During the advertisingwindow, the AP may advertise services which are available through theAP. This advertisement window may also include opportunities for STAs inthe BSS to send out advertisements for services which they offer. Insome aspects, the AP may schedule one advertising window foradvertisements from the AP, and another separate advertising window foradvertisements from other STAs. In some aspects, the AP may rebroadcastreceived queries during the advertising window to allow STAs that areservice providers to receive such queries.

A number of different types of frames may be used to schedule anadvertising window. For example, the AP may provide the scheduled timeof the advertising window in beacons and/or in probe response frames.The advertising window may be periodic and occur with some regularfrequency, or may be sporadic. For example, if the advertising window isperiodic, some frames sent by the AP, such as beacons or probe responseframes, may indicate a timing of the advertising windows and when theyare scheduled. For example, this timing may comprise information on whenthe next advertising window occurs, and the interval between advertisingwindows. Advertising windows may also be periodic. For example,advertising windows may occur based upon requests that the AP receivesfrom other devices for information regarding services. For example, ifan AP does not receive any requests from other devices regardingservices offered by the AP, the AP may schedule fewer advertisingwindows or no advertising windows. Advertising windows may also bescheduled more frequently when the AP receives a number of requests forone or more services. In some aspects, advertising windows may be bothperiodic and sporadic, such that periodic advertising windows will besent according to a schedule, and the AP may also supplement theseperiodic advertising windows with additional sporadic windows. Forexample, if a large number of devices request a listing of servicesoffered by the AP, the AP may schedule an additional advertising windowaccordingly.

Advertisements sent during the advertising window may includeadvertisements of some or all services offered by the AP, or on thenetwork of the AP. In some aspects, the AP may be configured to transmitadvertisements of services regardless of inquiries from other devices.For example, the AP may transmit a complete listing of services offeredduring some or all advertising windows, regardless of inquiries fromother devices. In some aspects, the AP may be configured to transmitadvertisements during the advertising window based on queries the APreceives from STAs. For example, if a STA requests information regardingone or more specific services, the AP may include information on theseone or more services during a next advertisement window, based on theSTA request. In some aspects, if advertisements are based on queriesreceived from STAs, the AP may buffer queries received from STAs untilan advertising window, and may transmit responses to each of thesequeries during that advertising window.

Advertising messages may be sent using a number of different types ofmessaging protocols. For example, Bonjour or Universal Plug 'n Play(UPnP) may be used to offer listings of services on an AP. Uniformresource identifiers (URIs) may also be used to offer listings ofservices on the AP. In some aspects, modified versions of one or more ofthese protocols, or other protocols, may also be used to transmitadvertising messages. Advertising messages may be sent as a number ofdifferent types of frames or messages. For example, advertising messagesmay be broadcast Access Network Query Protocol (ANQP) messages. Forexample, service discovery messages that are sent in response to an ANQPquery may be sent in broadcast during the advertising window.Advertising messages may also be transmitted as an unencrypted broadcastdata frame and/or a broadcast public action frame.

In some aspects, STAs may send ANQP queries at any time. The AP mayresponse with a come-back period that will point to the timing of afuture advertising window, or to the Target Beacon Transmit Time (TBTT)of the beacon, where the advertisement window will be advertised. STAsmay be configured to go to sleep after receiving the advertising windowschedule. Alternatively, a STA may derive the advertisement windowtiming implicitly from the Probe-Response or the Beacon that it alreadyreceived, if an advertisement window was already advertised. In thisaspect, a STA may go to sleep immediately after sending the query to theAP. In both of these aspects, responses to any query will be sent duringthe advertisement window.

In some aspects, the AP may use a delayed response to respond to STAqueries. For example, the AP may provide a minimum time to respond to aquery. This may be provided, for example, in the beacon or the proberesponse which advertises timing of the advertising windows. Forexample, the AP may transmit a minimum time to respond to a query in abeacon, along with information on the timing of advertising windows.This may enable a STA which sends a query regarding services offered bythe AP to determine when a response to that query may be received. Forexample, the STA may determine that a response to the query may bereceived during a next advertising window that is a minimum of at leastthe minimum time to respond to a query. For example, if the minimum timeto respond to a query is 300 ms, a STA that sends a query to the AP maydetermine that it will not receive a response until the firstadvertising window that is at least 300 ms from the time the query wassent. In some aspects, the AP may use this time to determine a responseto the query. For example, if a STA requests information regardingprinters on the AP, the AP may need to determine which, if any, printersmay be available through the AP. In some aspects, the minimum time torespond to a query may be transmitted to the STA from the AP in a proberesponse frame. For example, the STA may request information from the APregarding printers on the network in a probe request frame. The AP mayrespond with a probe response frame that includes timing information onwhich advertising window will contain this information. This timinginformation may include, for example, a minimum time to respond to aquery.

In some aspects, the use of an advertising window and a minimum responsetime may enable STAs to sleep until the appropriate advertising window.For example, a STA may transmit a query to the AP, and may go to sleepuntil an advertising window which occurs at a time after the minimumtime to respond to a query. For example, if the STA is aware of theminimum time to respond to a query, such as if the STA received thisminimum time in a beacon, the STA may sleep until an advertising windowafter transmitting a query. In some aspects, if the minimum time torespond to a query is contained in a probe response frame, the STA maysleep after receiving the probe response frame until the advertisingwindow.

In some aspects, the AP may be configured to re-transmit queries that itreceives during advertising windows. For example, a STA may query an APfor a service, such as a printer. An AP may or may not offer thisservice. The AP may retransmit this query during the advertising window,in order to allow other STAs to receive the query. This may allow, forexample, a STA which offers a printer to receive queries from otherSTAs, without requiring that the other STAs transmit a query at anycertain time, and without requiring the STA to be awake at all times.Instead, the STA offering a printer may be awake during the advertisingwindow, and may receive the retransmitted queries from the AP during theadvertising window. This may allow STAs which offer services andefficient way to find STAs which request services, and may also allowthese STAs to find each other without requiring that an AP storeinformation regarding each service available on each STA in the network.

FIG. 4 is a flowchart of a method for using advertising windows on anetwork, which may be used on a STA such as STA 106.

At block 405, the STA receives timing information from an access pointregarding an advertising window during which information on servicesoffered by one or more nodes on the network will be advertised. In someaspects, the STA may receive this information in a beacon from the AP.In some aspects, the STA may first transmit a probe request frame,containing a request for information on certain services on the network,such as a printer, and the AP may transmit a probe response frame whichincludes timing information regarding an advertising window. In someaspects, the timing information may include a minimum time to respond toa query. The STA may be configured to use this information to determinewhen a query submitted by the STA may be responded to. The STA may beconfigured to enter a low-power doze or sleep mode, or selectively powerdown some components, such as a receiver, after receiving the timinginformation until the time of the advertising window that may contain aresponse to the STAs query.

At block 410, the STA, during the advertising window, receivesinformation from the access point on services offered by one or morenodes on the network. In some aspects, this information may include aresponse to a query transmitted by the STA to the AP. In some aspects,the STA may also receive re-transmitted queries from the AP, the queriesoriginally being transmitted to the AP from another STA. In someaspects, the STA may be configured to respond to these re-transmittedqueries if the STA offers one or more services which are relevant to theSTA that originally transmitted the query to the AP. For example, theadvertising window may contain a portion of time during which the STAmay transmit advertising messages. These advertising messages mayinclude responses to queries and/or may include advertising messagesthat are generated by the STA autonomously to advertise services offeredby the STA.

As used herein, the term “determining” encompasses a wide variety ofactions.

For example, “determining” may include calculating, computing,processing, deriving, investigating, looking up (e.g., looking up in atable, a database or another data structure), ascertaining and the like.Also, “determining” may include receiving (e.g., receiving information),accessing (e.g., accessing data in a memory) and the like. Also,“determining” may include resolving, selecting, choosing, establishingand the like. Further, a “channel width” as used herein may encompass ormay also be referred to as a bandwidth in certain aspects.

The various operations of methods described above may be performed byany suitable means capable of performing the operations, such as varioushardware and/or software component(s), circuits, and/or module(s).Generally, any operations illustrated in the Figures may be performed bycorresponding functional means capable of performing the operations.

The various illustrative logical blocks, modules and circuits describedin connection with the present disclosure may be implemented orperformed with a general purpose processor, a digital signal processor(DSP), an application specific integrated circuit (ASIC), a fieldprogrammable gate array signal (FPGA) or other programmable logic device(PLD), discrete gate or transistor logic, discrete hardware componentsor any combination thereof designed to perform the functions describedherein. A general purpose processor may be a microprocessor, but in thealternative, the processor may be any commercially available processor,controller, microcontroller or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

In one or more aspects, the functions described may be implemented inhardware, software, firmware, or any combination thereof. If implementedin software, the functions may be stored on or transmitted over as oneor more instructions or code on a computer-readable medium.Computer-readable media includes both computer storage media andcommunication media including any medium that facilitates transfer of acomputer program from one place to another. A storage media may be anyavailable media that can be accessed by a computer. By way of example,and not limitation, such computer-readable media can comprise RAM, ROM,EEPROM, CD-ROM or other optical disk storage, magnetic disk storage orother magnetic storage devices, or any other medium that can be used tocarry or store desired program code in the form of instructions or datastructures and that can be accessed by a computer. Also, any connectionis properly termed a computer-readable medium. For example, if thesoftware is transmitted from a website, server, or other remote sourceusing a coaxial cable, fiber optic cable, twisted pair, digitalsubscriber line (DSL), or wireless technologies such as infrared, radio,and microwave, then the coaxial cable, fiber optic cable, twisted pair,DSL, or wireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,includes compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Thus, in some aspects computer readable medium may comprisenon-transitory computer readable medium (e.g., tangible media). Inaddition, in some aspects computer readable medium may comprisetransitory computer readable medium (e.g., a signal). Combinations ofthe above should also be included within the scope of computer-readablemedia.

The methods disclosed herein comprise one or more steps or actions forachieving the described method. The method steps and/or actions may beinterchanged with one another without departing from the scope of theclaims. In other words, unless a specific order of steps or actions isspecified, the order and/or use of specific steps and/or actions may bemodified without departing from the scope of the claims.

The functions described may be implemented in hardware, software,firmware or any combination thereof. If implemented in software, thefunctions may be stored as one or more instructions on acomputer-readable medium. A storage media may be any available mediathat can be accessed by a computer. By way of example, and notlimitation, such computer-readable media can comprise RAM, ROM, EEPROM,CD-ROM or other optical disk storage, magnetic disk storage or othermagnetic storage devices, or any other medium that can be used to carryor store desired program code in the form of instructions or datastructures and that can be accessed by a computer. Disk and disc, asused herein, include compact disc (CD), laser disc, optical disc,digital versatile disc (DVD), floppy disk, and Blu-ray® disc where disksusually reproduce data magnetically, while discs reproduce dataoptically with lasers.

Thus, certain aspects may comprise a computer program product forperforming the operations presented herein. For example, such a computerprogram product may comprise a computer readable medium havinginstructions stored (and/or encoded) thereon, the instructions beingexecutable by one or more processors to perform the operations describedherein. For certain aspects, the computer program product may includepackaging material.

Software or instructions may also be transmitted over a transmissionmedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition oftransmission medium.

Further, it should be appreciated that modules and/or other appropriatemeans for performing the methods and techniques described herein can bedownloaded and/or otherwise obtained by a user terminal and/or basestation as applicable. For example, such a device can be coupled to aserver to facilitate the transfer of means for performing the methodsdescribed herein. Alternatively, various methods described herein can beprovided via storage means (e.g., RAM, ROM, a physical storage mediumsuch as a compact disc (CD) or floppy disk, etc.), such that a userterminal and/or base station can obtain the various methods uponcoupling or providing the storage means to the device. Moreover, anyother suitable technique for providing the methods and techniquesdescribed herein to a device can be utilized.

It is to be understood that the claims are not limited to the preciseconfiguration and components illustrated above. Various modifications,changes and variations may be made in the arrangement, operation anddetails of the methods and apparatus described above without departingfrom the scope of the claims.

While the foregoing is directed to aspects of the present disclosure,other and further aspects of the disclosure may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow.

What is claimed is:
 1. A method for using advertising windows totransmit service information on a network, the method comprising:transmitting timing information regarding an advertising window duringwhich information on services offered by one or more nodes on thenetwork will be advertised; and during the advertising window,transmitting information on services offered by one or more nodes on thenetwork.
 2. The method of claim 1, further comprising receiving a queryfrom a wireless device for one or more services offered by one or morenodes on the network, and wherein transmitting information comprisestransmitting information on the one or more services.
 3. The method ofclaim 1, further comprising receiving from a wireless device a query forone or more services offered by one or more nodes on the network, andwherein transmitting timing information comprises transmitting timinginformation to the wireless device regarding an advertising windowcomprising a response to the query.
 4. The method of claim 1, furthercomprising during the advertising window, allowing other wirelessdevices to transmit information regarding services offered by the otherwireless devices.
 5. The method of claim 1, further comprisingconstructing a beacon or a probe response frame which contains timinginformation.
 6. The method of claim 1, further comprising transmitting aminimum time to respond to a query.
 7. The method of claim 1, furthercomprising: receiving a query for one or more services offered on thenetwork; and during the advertising window, re-transmitting the queryfor one or more services offered on the network.
 8. A wirelesscommunication device, the device comprising: a transmitter, thetransmitter configured to: transmit timing information regarding anadvertising window during which information on services offered by oneor more nodes on the network will be advertised; and during theadvertising window, transmit information on services offered by one ormore nodes on the network.
 9. The device of claim 8, further comprisinga receiver configured to receive a query from a wireless device for oneor more services offered by one or more nodes on the network, andwherein transmitting information comprises transmitting information onthe one or more services.
 10. The device of claim 8, further comprisinga receiver configured to receive a query from a wireless device for oneor more services offered by one or more nodes on the network, andwherein transmitting timing information comprises transmitting timinginformation to the wireless device regarding an advertising windowcomprising a response to the query.
 11. The device of claim 8, thetransmitter further configured to, during the advertising window, allowother wireless devices to transmit information regarding servicesoffered by the other wireless devices.
 12. The device of claim 8, thetransmitter further configured to construct a beacon or a probe responseframe which contains timing information.
 13. The device of claim 8,further comprising transmitting a minimum time to respond to a query.14. The device of claim 8, the wireless communication device furtherconfigured to act as an access point.
 15. The device of claim 8, furthercomprising: a receiver configured to receive a query for one or moreservices offered on the network; and the transmitter further configuredto: during the advertising window, re-transmit the query for one or moreservices offered on the network.